The hacky way is demonstrated in that GIF and operates even without spinning, although it'll look REALLY stupid.

The basic issue is that it's not really letting you walk on the wall; it's launching you into the air when you hit the wall. This works well for approximating quarter-pipe physics, but it doesn't work well once you try to continue the effect beyond the wall transfer.

Okay, I'm pretty late to the game and Jesus Christ do I love the look of this, remade sprites, possibly new shields, loops are now a thing in SRB2, weight and A PLAYABLE BIG THE CAT, WOO! In all seriousness I love what I'm looking at here, even though it's an April Fools prank/joke. I highly doubt there be actually new shields, and I definitely doubt there will be a playable 4th character, In this case Big. (Sonic & Tails together obviously doesn't count.) And I love the pun in the title, "A Big Announcement".